The impact of smoking on outcomes following anterior cervical fusion-nonfusion hybrid surgery: a retrospective single-center cohort study

Abstract

Background There is mixed evidence for the impact of cigarette smoking on outcomes following anterior cervical surgery. It has been reported to have a negative impact on healing after multilevel anterior cervical discectomy and fusion, however, segmental mobility has been suggested to be superior in smokers who underwent one- or two-level cervical disc replacement. Hybrid surgery, including anterior cervical discectomy and fusion and cervical disc replacement, has emerged as an alternative procedure for multilevel cervical degenerative disc disease. This study aimed to examine the impact of smoking on intermediate-term outcomes following hybrid surgery. Methods Radiographical and clinical outcomes of 153 patients who had undergone continuous two- or three-level hybrid surgery were followed-up to a minimum of 2-years post-operatively. The early fusion effect, 1-year fusion rate, the incidence of bone loss and heterotopic ossification, as well as the clinical outcomes were compared across three smoking status groups: (1) current smokers; (2) former smokers; (3) nonsmokers. Results Clinical outcomes were comparable among the three groups. However, the current smoking group had a poorer early fusion effect and 1-year fusion rate (P < 0.001 and P < 0.035 respectively). Both gender and smoking status were considered as key factors for 1-year fusion rate. Upon multivariable analysis, male gender (OR = 6.664, 95% CI: 1.248–35.581, P = 0.026) and current smoking status (OR = 0.009, 95% CI: 0.020–0.411, P = 0.002) were significantly associated with 1-year fusion rate. A subgroup analysis demonstrated statistically significant differences in both early fusion process (P < 0.001) and the 1-year fusion rate (P = 0.006) across the three smoking status groups in female patients. Finally, non-smoking status appeared to be protective against bone loss (OR = 0.427, 95% CI: 0.192–0.947, P = 0.036), with these patients likely to have at least one grade lower bone loss than current smokers. Conclusions Smoking is associated with poor outcomes following hybrid surgery for multilevel cervical disc disease. Current smokers had the poorest fusion rate and most bone loss, but no statistically significant differences were seen in clinical outcomes across the three groups.

Sex and gender determinants following spinal fusion surgery: A systematic review of clinical data

“…In addition, a significant difference in the early fusion process among current smokers, former smokers, and nonsmokers was detected for male patients, but no significant differences were founded at 1-year of follow-up. For female patients, statistical differences were found in both the early fusion process and the 1-year fusion rate ( 62 ).…”

Pulsed Electromagnetic Field Stimulation in Lumbar Spine Fusion for Patients With Risk Factors for Pseudarthrosis

“…43 Patients who are current smokers show reduced rates of fusion postoperation compared with nonsmokers. [44][45][46] One study showed pseudarthrosis 1 to 2 years postsurgery in 40% of smokers vs 8% in nonsmokers. 44 The current study results show no impact of known risk factors on fusion rate or patient-reported outcomes when treated with PEMF.…”

Risk factors affecting spinal fusion: A meta-analysis of 39 cohort studies

“…This meta-analysis showed that patients who smoked were at higher risk for fusion failure. The combined OR of 8 studies [32,36,38,41,44,46,48,49] was 1.57 (95% CI, 1.11 to 2.21; I 2 = 0.0%) (Fig 3). The trim-and-fill method was used to assess the robustness of the results, and we did not find potentially missing studies (S6 Table ).…”